WO1986005505A1

WO1986005505A1 - Polymeric dyes

Info

Publication number: WO1986005505A1
Application number: PCT/US1986/000161
Authority: WO
Inventors: Mohamed A. Elmasry
Original assignee: Minnesota Mining and Manufacturing Co
Current assignee: 3M Co
Priority date: 1985-03-11
Filing date: 1986-01-27
Publication date: 1986-09-25
Anticipated expiration: 1987-09-11
Also published as: JPH0662884B2; EP0217809B1; EP0217809A1; DE3667481D1; JPS62502121A; US4619990A

Abstract

Polymeric dyes having pendent chromophore groups which are selected from azo, tricyanovinyl, anthraquinone, methine, and indoaniline groups fall into two classes, ADABD condensation polymers, and ADBBD polymers derived from copolymerized ethylenically-unsaturated monomers. These compounds are useful as coloring and light-absorbing agents, particularly as the light-absorbing agents in thin optical recording layers.

Description

POLYMERIC DYES

FIELD OF THE INVENTION

This invention relates to polymeric dyes which contain a high proportion of certain classes of chromophore units. These compounds are useful as coloring and light-absorbing agents, particularly as the light-absorbing agents in thin optical recording layers.

BACKGROUND ART

Polymeric dyes are widely disclosed in the literature. Of particular importance is their use as food colorings and in the bulk and surface coloring of plastic objects and textile fibers. Their use as hair dyes, as tinting agents in paper manufacture, and in imaging systems as sensitizing agents is known in the art.

Kokai JA59-45195, laid open March 13, 1984, discloses hydrocarbon backbone polymers with pendent chrbmophores, e.g., azo, anthraquinone, indigoid, cyanine, etc. Polymers are thermoplastic and film-forming, and are useful as thin coated layers for deformation optical recording.

Kokai JA59-62188, laid open April 9, 1984, discloses various polymer backbones , e . g . , polyester , polyurethane , polyamide, vinyl polymers, etc., with pendent phthalocyanine (preferably metal) chromophores. Polymers are thermoplastic and film-forming, and useful as thin coated layers for deformation optical recording.

Representative of polymeric dyes for food colorings are those disclosed in U.S. Patent No. 4,206,240. Here pendent chromophore groups such as anthraquinones, azo dye moieties, etc., are linked at intervals to a hydrocarbon polymer backbone through nitrogen atoms which may be in the backbone or pendent from it. Solubility in aqueous systems is frequently a requirement of such food colorings and U.S. Patent Nos. 4,233,328 and 4,169,203 disclose such polymeric dyes. Polymeric dyes used in dyeing textiles and coloring textile polymers in bulk are disclosed in U.S. Patent No. 3,232,691. These are derived from acrylate or methacrylate monomers with pendent chromophore groups of azo, anthraquinone, or triarylmethane dye moieties.

Hair dying compositions containing polymeric dyes are described in U.S. Patent Nos. 4,182,612 and 4,228,259. These dyes have polyethyleneimine type backbones with chromophores such as azo, anthraquinone, etc., pendent from the backbone nitrogen atoms. Graft copolymerized pigments for use as fillers in paper making are described in U.S. Patent No. 4,369,292.

In silver halide photography polymeric color couplers derived from ethylenically-unsaturated monomers are disclosed in U.S. Patent No. 4,367,282. Polymeric color couplers are also disclosed in U.S. Patent No. 3,743,503 as developable coloring agents in electrographic toners.

U.S. Patent No. 4,365,012 discloses photochromic cyclic polyimides for optical recording.

SUMMARY OF THE INVENTION

Briefly, the present invention provides novel polymeric dyes capable of undergoing thermoplastic deformation by a focused laser beam when in a layer of thickness in the range of 0.1 to 100 micrometers and having an absorptivity in the range of 10 to 250 Lg^-1cm^-1. They are film-forming, thermally- and light-stable, and solvent-coatable. The polymeric dyes of the invention are useful as optical recording layers for which purpose they do not require the addition of a binder. The polymeric dye layer when used as an optical recording medium can be a thermoplastic, light absorbing layer comprising at least 10 percent by weight of at least one polymeric dye of the instant invention. The polymeric dyes of the invention are capable of absorbing radiation in the visible range (i.e., 400-700 nm, preferably with peak absorptions in the range of 450-650 nm). The dyes, although sufficiently absorbing of wavelengths in a selective absorption region to allow thermoplastic deformation of the layer by a focused laser beam, are sufficiently stable so as not to be destroyed under these conditions.

It is known in the art to use molecular dyes dispersed in thermoplastic binders for deformation recording (e.g, U.S. Patent Nos. 4,364,986 and 4,380,769). The use of polymeric dye layers without any binder has the following advantages over that art.

1. High chromophore concentrations can be obtained without the special solubility relationships required between dye and binder. 2. High clarity of the layer is easily obtained thus giving less background noise. 3. The chromophores do not migrate or become lost from the layer during the thermoplastic action, thus facilitating reuse. 4. There is no danger of dye crystallization on storage. 5. Polymeric dyes are frequently more stable to heat than the individual dyes, e.g., IR chromophores. In general, the polymeric dyes of the invention are linear homopolymers of chromophoric moieties, or linear random or condensed copolymers or homopolymers of chromophoric and non-chromophoric moieties or more than one chromophoric moiety. In the visible and near UV regions representative dyes can consist of a polymeric backbone containing at least one of phenylene and imino groups, with chromophores selected from at least one of the azo dyes and tricyanovinylated aryl compounds. As used in this application: "thermoplastic deformation" means a stable alteration of the form of a plastic substance under the influence of heat, the altered form being capable of returning to its unspoiled state by further application of heat;

"polymeric dye" means a dye molecule having at least five recurring monomeric units;

"chromophore" means a radiation-absorbing group of atoms that provides a colored molecule;

"auxochromic group" means a group of atoms that intensifies the color of a chromophore, i.e., usually a substituent on a chromophore; and

"alkyl", "alkoxy", "alkylamino", "dialkylamino" mean groups containing 1 to 6 carbon atoms for each "alkyl" unless otherwise specified,

"methine" means a group to provide a moiety

with alternating single and double bonds; and

"tricarbocyanine" or "carbocyanine" means a seven-membered methine chain connecting two heterocyclic nitrogen-containing groups where the nitrogen atoms are part of the conjugated chain; and

"absorption coefficient", b, means 1n T.

DETAILED DESCRIPTION OF THE INVENTION

Polymeric dyes for the practice of this invention having pendent chromophore groups selected from azo, tricyanovinyl, anthraquinone, methine, and indoaniline groups fall into two classes, [A] condensation polymers, and [B] polymers derived from copolymerized ethylenically-unsaturated monomers, as follows:

[A] This class comprises polymeric dyes of the general formula

wherein n can be an integer from 5 to 100,000, preferably from 5 to 10,000, which are formed as condensation polymers of diacids, dihaloformates, or diisocyanates having the formulae I below, and dihydroxy compounds with pendant arylamine groups having the formula II below which are capable of condensation polymerization with compounds of formulae I. Formulae I monomers can be

where

L can be -Cl or -Br, and

R can be an aliphatic (straight-chain, branched, or cyclic) or aromatic (single or fused ring) hydrocarbon with up to 30 carbon atoms. Formula II monomers can be

where

Z is a linking group which can be a substituted or unsubstituted phenylene or naphthylene group wherein the substitution groups are -Br, -F , -OH, alkyl, alkoxy, alkylamino, dialkylamino, -NH₂,

-NO₂, phenyl, carbamoyl, -CN, carbalkoxy

sulfonyl, sulfamyl, and sulfamido,

Y completes a chromophore chosen from classes 1) to 4) below, and

X can be condensation residues or

Chromophores and linking groups represented by Z-Y include: 1) Azo groups where Z is as defined above, and Y can be -N=N-D or -N=N-G-N=N-D, and D can be an aromatic nucleus of 1 to 5 rings (fused or connected by single bonds), or a heterocyclic ring of 4, 5, or 6 members containing one to four or more atoms of -N-, -S-, and non-peroxidic atoms -O- optionally bearing one or more auxochromic groups as substituents chosen from groups such as -Cl, -Br, -F, -OH, alkyl, alkoxy, alkylamino, dialkylamino, -NH₂, -NO₂, phenyl,

carbamoyl, -CN, carbalkoxy

sulfonyl, sulfamyl, and sulfamido and G is a phenylene or naphthylene group,

2) Tricyanovinyl groups where Z can be as defined above, and

3) Anthraquinone groups where Z can be as defined above or can be a single bond, and

where R¹ can be -OH, -NH₂, alkylamine, dialkylamino, or arylamino where aryl is phenyl or phenyl substituted by auxochromic groups as defined for use on D as defined in 1) above, R² and R³ independently can be auxochromic groups as defined for use on D as defined in 1) above;

4) Polymethine and methine groups where Z can be as defined above for [A]l), and

in which Q can be -S-, -Se-, or -O-.

R⁴ can be an auxochromic group as in

1) above, R⁵ can be alkyl (C₄-C₁₈) or an anion group as in zwitterion moieties in which case W is not present

W is an anion such as Cl-, Br-, ClO₄-, CDSO₃-, BF₆-, PF₆-, CH₃SO₃-, C₂F₅C₆H₁₀SO₃-, and other anions commonly used with methine dyes. General preparative methods for class [A] polymers having polyester, polycarbonate, or polyurethane backbones, as exemplified using various chromophores are as follows:

(a) Polyester or polycarbonate copolymers (azo dyes) A mixture of 0.01 mole of the arylazophenyl- iminodiethanol dye, 0.01 mole of aryl diacid chloride or aryldichloroformate, 40 mL of 1,2-dichloroethane, and 3 mL (0.038 mole) of pyridine was refluxed for one hour, then cooled, coagulated in 300 mL of ethanol in a home blender, and filtered off. The polymeric dye was returned to the blender, blended twice with water, and dried. (b) Polyurethane copolymer (azo dyes)

A solution of 0.1 mole of the arylazophenyl- iminodiethanol dye in 40 mL of dry dimethylsulfoxide was added all at once to a solution of 0.1 mole of diisocyanate in 40 mL of cyclohexanone. The reaction mixture was heated while stirring for three hours at 115°C, cooled, and the polymeric dye extracted as in (a) above.

(c) Polyurethane copolymer-tricyanovinyl dye A solution of 0.1 mole of the aryliminodiethanol in 40 mL of dry dimethylsulfoxide is added to a solution of 0.1 mole of diisocyanate in 40 mL of cyclohexanane. The reaction mixture is heated with stirring for three hours at 115°C and the uncolored polymeric dye precursor is extracted as in (a) above. Tricyanovinylation of the non-chromophoric polymer to give the dye may be accomplished by reacting them with tetracyanoethylene in dimethyl formamide or pydrine at. 50-55°C for 1/2 hour.

(d) Polyester copolymer-methine dye

Phenyliminodiethanol is reacted with an aryldiacid chloride as in (a). The uncolored polymer is 100% formulated with excess dimethylformamide in the presence of POCI₃ by conventional technique, and then condensed with a compound of the structure

in which Q, R⁴, R⁵ as defined in [A]4) above, to give a polymethine dye/polyester copolymer.

(e) Polyester, polycarbonate, polyurethane copolymer-anthraquinone dyes Anthraquinone precursors are commercially available as dye intermediates, such as

wherein R¹ is as defined above, and may be condensed directly with diacid halides, dihaloformates, or diisocyanates as indicated above.

[B] This class comprises copolymers (preferably random) having 5 to 100,000 monomeric units derived from ethylenically-unsaturated monomers, at least one having formula III and at least one having formula IV

III - any ethylenically-unsaturated monofunctional monomer not including any chromophoric moieties, for example, (meth)acrylamide or

(meth)acrylate monomer CH₂=CH-OR⁸ vinyl ether monomer

vinyl ester monomer

CH₂=CR⁶-CN meth(acrylonitrile) monomer where R⁶ can be -H or -CH₃

R⁷ can be -OR⁸ or -NHR⁸ R⁸ can be alkyl (C₁-C₁₈)

IV - chromophore-containing ethylenically-unsaturated monomers including

(meth)acrylate dye

vinyl ester dye CH₂=CH-O-R⁹-Z-Y vinyl ether dye where R⁶ can be -H or -CH₃ independently of formula III monomer Z-Y can be chromophore and linking group as defined in classes [B] 1)-2) below, similar to [A]1) to [A]4),

Z can be those radicals defined in the equivalent classes of [A] and, R⁹ can be a linking group defined individually for chromophores in [B]1) and [B]2) below.

Examples of dyes in Class [B] include

1) Tricyanovinyl dyes

Z and Y can be defined as in [A]2), and

R⁹ can be wherein R¹⁰ can be -H

or alkyl (C₁-C₈), and r can be an integer 1 to 6;

2) Methine or polymethine dyes

Z and Y can be defined as in [A]4), and R⁹ as in [B]1);

General preparative method for Class [B] poly(meth)acrylate polymers is as follows:

(a) Copolymerization of at least two monomers in any relative amounts

(i) methine dye monomer, indoaniline dye monomers, or N-alkyl-N-(meth)-acryloyloxyethyl-aniline(toluidine) (ii) (meth)acrylate comonomer with 1 weight percent 1-dodecane mercaptan and 1 weight percent of azobisisobutylnitrile as initiator (percent related to total monomers) in toluene was heated at 79°c ± 1°C for 5 hours. When a dye (meth)acrylate is used the resulting solution of polymeric dye in toluene may be coated as it is or may be extracted by coagulating in 300 mL of ethanol in a home blender, and then filtered and dried, (b) Tricyanovinylation of the non-chromophoric polymers prepared in (a) (ii) immediately above may be accomplished by reacting them with tetracyanoethylene in dimethylformamide or pyridine at 50-55°C for about 1/2 hour. Other polymeric dyes with other chromophores can be prepared as is known in the art. It is also within the scope of the present invention to polymerize two or more different chromophoric monomers.

Preferred examples of polymeric dye units of classes [A] and [B] for use in optical recording layers are as follows:

(1) Azo dye polymer units of the class [A]1) having the formula

where X can be

_ι >_ι

and R²² can be -OCH₃, -Cl, or -H, these three R groups providing peak absorptions at

488, 514, and 475 nm, respectively, m is an integer of 1 to 18, n is the number of units in the polymer chain is in the range of 5 to 100,000 or more, which are prepared by copolymerization of an azo dye of the formula X below, with the following six representative monomers (IX-a, IX-b, IX-c, IX-d, IX-e, and IX-f)

wherein m is an integer 1 to 18 X

wherein R²² is as defined above.

These condensation polymerizations necessarily produce alternating chains derived from monomers IX and X. Final average molecular weights are often fairly well defined at between 8,000 and 20,000. These polymeric azo dyes have good solubility in cyclohexanone and chlorinated solvents and can be spin-coated or dip-coated from a solution to give smooth, transparent, uniform films with no flaws. They absorb in the visible range with an absorptivity as defined below at the peak wavelength of 50 Lg^-1cm^-1, which translates to a layer absorption coefficient of about 6-8xl0⁴ cm^-1.

(2) Tricyanovinylated polyaryliminodiethanol esters of the class [A]2) having units of the formula

where R is any aliphatic or aromatic hydrocarbon preferably with up to 20 carbon atoms, and n can be an integer of 5 to 100,000. An Example of such polymeric dyes in which

R²⁰ is -CH₃, -H, or -OCH₃,

has λmax = 519 nm in methyl ethyl ketone (MEK)

These are made by reacting a compound of the formula

OCN-R-NCO

wherein R is as defined above,

with the chromophore precursor used by Sulzburg & Cotter, Macromolecules 2 (2) March/April 1969 (page 146) having the formula

giving a polymer which is then reacted with tetracyanoethylene in dimethyl formamide or pyridine at 50-55°C for about 1/2 hour to give a polymeric dye of molecular weight in the range 15,000 to 50,000.

(3) An example of an [A]3) novel anthraquinone dye of the invention has units of the formula

wherein n is an integer of 5 to 100,000.

(4) Novel polymeric dyes of the class [A]4) derived from styryl dyes have units of the formula

where X is a non-chromophoric group as defined above in preferred examples [A] (1) above. and -Q is -S-, -Se-, or -O-,

R²¹ is alkyl (C₁-C₂₀), and n is 5 to 100,000.

An example in which Q is R²¹ is ethyl, W is the

anion I-,

gives O

This dye was prepared as shown in the scheme below;

POCI ₃ DMF

wherein n can be an integer of 5 to 100,000, and which has max = 546 nm.

NMR showed 100 percent formylation of the benzene ring.

(5) Novel polymeric dyes of the class [B]1) can be prepared by starting with the monomer

wherein

R⁶ is -H or -CH₃, R²¹ is alkyl, R³ = -CH₃, -H, or -OCH₃, and R²⁰ is independently -CH₃, -H, or -OCH₃.

Polymerization of these ethylenically-unsaturated monomers is by standard methods well known in the art except that the addition of a chain transfer agent such as l-dodecanemercaptan is needed to prevent crosslinking through the reactive hydrogen on the methylene group next to the imide nitrogen. Tricyanovinylation of the obtained polymer may be accomplished by reaction with tetracyanoethylene in dimethyl formamide or pyridine at 50-55°C for about 1/2 hour, and can be used, for example, to prepare the following terpolymer:

wherein n is 5 to 100,000, and in which the three pendent chains are disposed at random along the backbone.

(6) An example of a polymeric dye of class [B]2) can have the formula

wherein n can be an integer of 5 to 100,00.0. When used as light absorbing agents in optical recording layers, the concentration of chromophores in the polymeric dye should be as high as possible in order to attain high coated layer absorption coefficients in the range of 10³ to 10⁵ cm^-1. Non-chromophoric monomers may be used in the copolymers to assist in the providing of the required physical properties such as film-forming, non-crystallinity, T_G, solvent solubility, adhesion to substrate, etc. In some cases however it may be possible to produce satisfactory physical properties from chromophoric monomers alone.

It is preferable that the chromophore chosen should have a high molar extinction coefficient so that the absorption coefficient of the layer is not unduly limited by the need to copolymerize with non-chromophoric monomers. Although with normal molecular chromophores it is common to describe their light absorbing efficiency by the molar extinction coefficient, it is neither satisfactory nor reliable to use this measure with polymeric materials. A useful measure of the absorption of polymeric dyes in bulk is given by the absorptivity, a, in units Lg^-1cm^-1 where a expressed in terms of the transmission factor T of a solution of concentration c g/L and thickness d cm is given by T Values of absorptivity are in the

range of 15 to 100 Lg^-1cm^-1, and preferably 25 to 75 Lg^-1cm^-1, and have been obtained with the polymeric dyes of the invention.

The polymeric dyes of this invention should be substantially linear in their form. The acceptable range of polymer chain lengths is also determined by the resultant physical properties, but chains containing about 5 chromophore units upwards to about 100,000 chromophore units will be useful. The molecular weight range can be from about 500 to about 10,000,000 but a preferred range is from about 5000 to about 100,000. The most preferred range is from 7,000 to 30,000. The preferred chromophore content is in the range of 40 to 100 mol percent. In optical recording with lasers, it is particularly important to be able to choose the wavelength of peak absorption of the absorbing material in a wide range of wavelengths. By suitable choice of the chromophores in the present invention, the range covered can be from 300 nm to 1000 nm. It is possible to have more than one absorption peak either by choice of the chromophore or by polymerization using more than one type of chromophore. Non-chromophoric monomers useful in preparing the polymers of the invention are disclosed above.

At the exposing laser wavelength within the dye absorption band, the absorption coefficient of the layer should be at least 10³ cm^-1 in order that images may be formed when laser beams in the milliWatt range are used rather than higher powers.

The polymeric dyes of the instant invention can also be useful as coloring agents for foods, plastics, textile fibers, paper and in imaging systems. Objects and advantages of this invention are further illustrated by the following examples, but the particular materials and amounts thereof recited in these examples, as well as other conditions and details, should not be construed to unduly limit this invention.

EXAMPLES

Example 1

The following polymeric azo dyes were prepared using different non-chromophoric monomeric links A. The resulting Tg values are given. ελ_max in the range 2.5-3.0 x 10⁴ L-mol^-1 cm^{- 1} based on a molecular weight of one unit of the polymer were obtained.

, having a

polycarbonate where

polyurethane where 3

urethane carbonate

Example 2

Comparative tests of the polymeric dyes of the invention (see below) against three materials known in the art (1. trilayer disk, 2. photochromic layer disk, 3. thermoplastic layer having soluble dye therein) were made in terms of carrier to noise ratio (C/N) for a range of recording beam power levels. The measurements were carried out using an acousto-optic modulator giving short repetitive pulses of laser light of 50 ns duration at a frequency of 10 MHz. Suitable optics imaged the light onto a layer coated onto each of the disks. The results showed a threshold response characteristic commonly found in Trilayer disks as opposed to a broad response of both the photochromic and thermoplastic + dye systems. The polymeric dye also showed a carrier to noise ratio of 55 dB which is close to that of the Trilayer disk and much higher than the others.

The polymeric dye used in these tests was

wherein n is an integer in the range of 5 to 100,000.

Various modifications and alterations of this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention, and it should be understood that this invention is not to be unduly limited to the illustrative embodiments set forth herein.

Claims

What Is Claimed Is:

1. A polymeric dye selected from classes [A] and [B] wherein Class [A] is a dye polymer comprising repeating units of the formula

said repeating units numbering between 5 and 100,000,

wherein X is

R is a hydrocarbon chain with up to 30 carbon atoms selected from the class consisting of straight chain aliphatic, branched chain aliphatic, cycloaliphatic, single or fused ring aromatic, Z is (1) substituted or unsubstituted phenylene or naphthylene, or (2) a single bond when Y is an anthraquinone moiety, Y is a chromophore moiety selected from the group consisting of an azo moiety, a tricyanovinyl moiety, an anthraquinone moiety, and a methine moiety, and Class [B] is a dye polymer consisting essentially of units of copolymers derived from ethylenically-unsaturated monomers, at least one of which is a monomer of subclass III and at least one of which is a monomer of Class IV wherein

Subclass III is a non-chromophore-containing monomer selected from the group consisting of

(raeth)acrylate monomer, (meth)acrylamide monomer, vinyl ether monomer, vinyl ester monomer, and meth(acrylonitrile) monomer, and Subclass IV is selected from the group consisting of (meth)acrylate dye, vinyl ester dye, and vinyl ether dye, with the proviso that Class IV monomers contain a pendent tricyanovinyl, methine, or polymethine dye group.

2. The polymeric dye of Class [A] according to Claim 1 wherein when the moiety Z is phenylene or naphthylene it is substituted by one or more substitutents selected from the group consisting of -Cl, -Br, -F, -OH, alkyl(C₁-C₆), alkoxy, alkylamino, dialkylamino, -NH₂, -NO₂, phenyl, carbamoyl, -CN, carbalkoxy, sulfonyl, sulfamyl, and sulfamido.

3. The polymeric dye of Class [A] as recited in Claims 1 and 2 wherein the chromophore is selected from the class consisting of

1) Azo groups where Y = -N=N-D or -N=N-G-N=N-D and D is an aromatic nucleus of 1-5 rings, or a heterocyclic ring of 4, 5, or 6 members containing one or more atoms of N, S, and non-peroxidic 0 atoms optionally bearing one or more auxochromic groups as substituents selected from the group consisting of -Cl, -Br, -F, -OH, alkyl (C₁-C₆), alkoxy, alkylamino, dialkylamino, -NH₂, -NO₂, phenyl, carbamoyl, -CN, carbalkoxy, sulfonyl, sulfamyl, and sulfamido and G is a phenylene or naphthylene group; 2) Tricyanovinyl groups where

3) Anthraquinone groups where

where R¹ can be OH, NH₂, alkylamine, dialkylamino, or arylamino where aryl is phenyl or substituted phenyl; R² and R³ are independently auxochromic groups as illustrated in 1) above, and Z is as previously defined and is also a single bond; 4) Methine groups wherein

in which Q is

3 ₂ -S-, -Se-, or -O-,

R⁴ is an auxochromic group -Cl, -Br, -F, -OH, alkyl, alkoxy, alkylamino, dialkylamino, -NH₂, -NO₂, phenyl, carbamoyl, -CN, carbalkoxy

sulfonyl, sulfamyl, and sulfamido

and G is a phenylene or naphthylene group, R⁵ is alkyl (C₁-C₁₈) or an anion group as in zwitterion dyes in which case W is not present, W is a dye anion.

4. The polymeric dye of Class [B] according to claim 1 wherein

Subclass III is selected from the group consisting of

^/

CH₂=CH-OR⁸ ,

CH₂=CR⁶-CN , wherein R⁶ is H or CH₃,

R⁷ is -OR⁸ or -NHR⁸,

R⁸ is alkyl (C₁-C₁₈), and

Subclass IV is selected from the group consisting of

and

wherein R⁶ is independently -H or -CH₃, Z is a substituted or unsubstituted phenylene or naphthylene,

Y is a chromophore moiety selected from the group consisting of a tricyanovinyl moiety, a methine moiety, and a polymethine group, and

R⁹ is wherein R¹⁰ is -H or

alkyl (C₁ to C₈), and r is an integer 1 to 6.

5. A polymeric dye polymer having repeating units of the formula

said repeating units numbering between 5 and 100,000,

wherein X is

R is a hydrocarbon chain with up to 30 carbon atoms selected from the class consisting of straight chain aliphatic, branched chain aliphatic, cycloaliphatic, single or fused ring aromatic, Z is (1) a substituted or unsubstitutec phenylene or naphthylene, or (2) a single bond, when Y is an anthraquinone moiety, Y is a chromophore moiety selected from the group consisting of an azo moiety, a tricyanovinyl moiety, an anthraquinone moiety, and a methine moiety.

6. A polymeric dye according to CLaims 1 to 3, and 5 prepared by the condensation of a compound chosen from the group consisting of

and OCN-R-NCO, wherein L = -Cl or

-Br, R = a straight-chain, branched, cyclic aliphatic or single or fused ring aromatic hydrocarbon with up to 30 carbon atoms, with a compound having the general structure

wherein Z is (1) a substituted or unsubstituted phenylene or naphthylene group, or (2) a single bond, when Y is an anthraquinone moiety, Y completes an azo, tricyanovinyl, anthraquinone, polymethine or methine chromophore.

7. A polymeric dye according to Claims 1 and 4 prepared by the copolymerization of at least two monomers, at least one of which is chosen from each of a) and b) wherein

a) is

CH₂=CH-OR⁸, or

CH₂=CH-CN,

and b) is

CH₂=CH-O-R⁹-Z-Y wherein R⁶ is -H or -CH₃,

R⁷ is -OR⁸ or -NHR⁸,

R⁸ is alkyl of 1 to 18 carbon atoms,

R⁹ is a linking group, Z is a substituted or unsubstituted phenylene or naphthylene, and

Y is a tricyanovinyl, methine or polymethine chromophore group.

8. The polymeric dye according to any preceding claim which is capable of undergoing thermoplastic deformation by a focused laser beam.

9. The polymeric dye according to any preceding claim which when in a layer of thickness in the range of 0.1 to 100 micrometers has an absorptivity in the range of 10 to 250 Lg^-1cm^-1.

10. The polymeric dye according to any preceding claim which is film-forming.